2 5 dimercapto 1 3 4 thiadiazole synthesis July 8, 2019 16 32 64 128 2 5-dimercapto-1 3 4-thiadiazole 2 5-dimercaptoterephthalic acid 2 3-dimercapto-1-propanol synthesis 2 4-dimethyl-3 5-dicarbethoxypyrrole